STANDARDIZATION OF FIXATION, PROCESSING AND STAINING METHODS FOR THE CENTRAL-NERVOUS-SYSTEM OF VERTEBRATES

This paper reports the standardization of methods used for processing and embedding various vertebrate brains of different sizes in paraffin . Other technical details developed for avoiding frequent difficulties arising during laboratory routine are also reported. Some modificatio ns of the Nissl and Kluver-Barrera staining methods are proposed. Thes e modifications include: 1) a Nissl stain solution with a rapid and ef ficient action with easier differentiation; 2) the use of a cheap micr owave oven for the Kluver-Barrera stain. These procedures have the adv antage of permitting Nissl and Kluver-Barrera staining of nervous tiss ue in about five and fifteen minutes respectively. The proposed proced ures have been tested in brains obtained from fish, amphibians, reptil es and mammals of different body sizes. They are the result of our lon g experience in preparing slides for comparative studies. Serial secti ons of excellent quality were regularly obtained in all the specimens studied. These standardized methods, being simple and quick, are recom mended for routine use in neurobiological laboratories.